Choose from the given options one that is opposite in meaning to "Deter"

Encourage

The word that is opposite in meaning to deter is encourage.

• Deter means to discourage or prevent someone from doing something.
• Encourage means to give someone the courage or confidence to do something.

The other words in the options have different meanings to deter. Defeat means to win a victory over someone or something. Discourage means to make someone less likely to do something. Dishearten means to make someone lose hope or confidence.